Evolution: phylogenetic trees & morphological structures

• Biologie
• Middelbare school
• vwo
• Leerjaar 4

Evolution

Chapter 12&13 

Lesson 3: phylogenetic trees & morphological structures

In a certain population, disruptive selection is occurring. In this population, which is most likely to survive?

1. organisms with average traits
2. organisms with extreme traits
3. organisms that sexually select
4. organisms that are small

A scientific name contains information about its:

1. family and species
2. genus and species
3. phylum and order
4. class and family

Cheetahs nearly became extinct but recovery efforts managed to save them. Now, most cheetahs are genetically identical. This is due to:

1. gene flow
2. the bottleneck effect
3. selective migration
4. random mating

Members of different species do not normally produce offspring due to:

1. differing courtship rituals
2. varying breeding times
3. gamete incompatibility
4. all of these

Learning objectives

• Read and create phylogenetic trees
• Describe convergent and divergent evolution
• Distinguish between analogous and homologous structures
• Describe the significance of morphological structures as evidence of evolution 

Phylogenetic tree

Tips for reading trees

• Same, but different style
  
  
  
  
• Same, but turned at 
  branching point 

According to this tree, sharks are MOST closely related to which organism?

1. amphibians
2. ray-finned fish
3. primates
4. birds

According to this tree, birds are LEAST closely related to which organism?

1. amphibians
2. ray-finned fish
3. primates
4. sharks

What is the most recent common ancestor of C and D?

1. 1
2. 2
3. 3
4. 4

Building a tree

Lamprey is the outgroup: most distantly related, starting point





Trait shared by the largest group
Parsimony: simplest solution is most likely

Building a tree

Interesting structures

• Homologous: divergent evolution
  similar origin, different function
• Analogous: convergent evolution
  different origin, similar function

Vestigial organs

No apparent function, residual parts of an ancestor

Which type of evolution shows a common ancestor?

1. convergent
2. divergent
3. adaptive radiation
4. both adaptive radiation and divergent

In convergent evolution, organisms share physical similarities because they

1. have a common ancestor
2. live in the same environment
3. develop homologous structures
4. are closely related

Flying fish, flying birds, and bats are examples of which of the following?

1. convergent evolution & homologous structures
2. convergent evolution & analogous structures
3. divergent evolution & homologous structures
4. divergent evolution & analogous structures

Match the image to the evolution pattern

1. A=convergent B=divergent C=adaptive radiation
2. A=adaptive radiation B=convergent C=divergent
3. A=divergent B=convergent C=adaptive radiation
4. A=divergent B=adaptive radiation C=convergent

Homework

Complete the worksheet phylogenetic trees & morphological structures